1. Field of the Invention
The present invention relates to a chronograph timepiece having a time indicating function and a time measuring function.
2. Description of the Related Art
There has been developed a multi-function timepiece in which a plurality of drive motors are mounted in order to individually drive a plurality of indicator hands and which is endowed with a time information indicating function as the basic function and, further, with a chronograph measuring function for performing time measurement (e.g., see Japanese Patent No. 3,019,324).
As a drive power source for the electrical components such as the motors, a battery is mounted in the above multi-function timepiece, and, in determining the battery service life, it is common practice to perform calculation based on an operational current value and a battery capacitance value. In the case of a chronograph timepiece, it is common practice to calculate the battery service life on the assumption that the requisite power consumption for the time indicating operation corresponds to 24 hours per day and that the requisite power consumption for the chronograph measurement operation corresponds to one hour per day.
However, the drive pulses for the chronograph hand movement motor are of high frequency, so that, in many cases, there are used drive pulses of higher power effective value than the drive pulses for the time hand movement motor. Thus, the chronograph function consumes the power of the battery in large proportion; in a case in which the chronograph timepiece is put to daily use without much utilizing the chronograph function, the time portion causing shortage of use of the chronograph operation during a predetermined period of time serving as a condition for battery service life calculation will constitute a use-shortage period; due to the influence of this use-shortage period, the battery consumption becomes too small, and the battery service life becomes excessively long, with the result that the reliability service life of the battery is exceeded to generate liquid leakage, thereby causing a serious damage to the chronograph timepiece.